There is a new page filled with information that may or may not be potentially useful: http://musicgames.wikidot.com/hub:tag and it explains the meaning of all currently used game tags. Information about each tag also shows after clicking in the tag-cloud.
Some parts indeed provide clarification (for tags used inconsistently before), some are unfortunately just fillers, for completion.

SoMiDo, sorry, I removed a lot of your tags, as they were very specific only to your projects… ;)

As always all suggestions welcome! Of course new tags may be added, but let's try to make them covering at least few activities and not overlap with currently established.

EDIT: When tags are set, the interesting possibility appeared.
We can now select multiple tags at once. This will probably prove more useful with more games in the library.
See it for example at the bottom of the http://musicgames.wikidot.com/hub:tag page.